Moisture meter for concrete aggregate



f'Aprl 28', 1931. R E. RoBB MOISTUHE METER. FOR CONCRETE AGGREGATE 2 Sheets-Sheet 1 Filed Aug. 1l, 1928 INVENTOR. foar/w' E. Faas.

Amun:

April 1931.

R. E.- ROBB MOISTURE METER FOR CONCRETE AGGREGATE Filed Aug. 11, 1928 z'sneets-snet- 2 I N V EN TOR. Raaf/er E. F055.

A TT ORNE Y5.

Patented Apr. 28, 1931 siI :E

ROBERT E. ROBB, OF EVANSVILL, INDIANA MOISTURE METER FOR CONCRETE AGGREGATE Application led August 11, 1928. Serial No. 298,945.

T he object of this invention is to provide means whereby a mechanic or any unskilled or uneducated person can readily and accurately predetermine the amount of moisture in the sand,` gravel, stone or other aggregate or non-soluble, granular materia-l which is to be used for concrete construction or thelike, and to do this without drying a sample of the material and without having to resort to the use of any computations, charts, figures, tables or other mechanical aid. This enables such mechanic or other person to scientifically and accurately make Pconcrete of the desired quality without re- -quirement on his part of any special education, training or skill.`

The operation and use of this apparatus depends upon the relative specific gravity of the material rather'than upon the volume or the Ivoids or other features of the aggregate or material. It involves water or other liquid displacement, but more than that as it depends' ultimately upon the relative specific graif'ity of the material.

Another feature of the invention is to provide suoli apparatus in s iinple form whereby it can be coinpactly assemble-d for easy transportation byhand or otherwise and be used atany point or time without inconvenience. n

Another feature of the invention is to pro-` vide such apparatus that can be used to prepare a test standard or a condition of the apparatus adapting it to be maintained and used repeatedly thereafter 4for determining the moisture in aggregate of the same kind of aggregate used in making the test standard. In other words, a standard test can be made by using a known weight of dry aggregate and the apparatus will be set for use in repeatedly determining the moisture in moist aggregate to be tested thereafter when, where and as often as described. In other words, the same apparatus is used in making the stan-dard test and also in the final tests of the moist aggregate. c

Furthermore, the same apparatus can be usedfor determining the fineness modulus or grading factorof aggregate being used in concrete Work.

The full nature of this inventionwill be more fully understood from the accoinpanying drawings and the following description and claims:

In the drawings, Fig. l is a central vertical section of the main vessel in said apparatus and the handle or loop for supporting the same, water being shown therein up to the lower pet cock. Fig. 2 is a similar section of sai-d main vessel with dry aggregate added to the water previously therein and suspended from one end of a counterbalancing beam and sliding counterpoise beam shown partly in elevation and partly in section, which is supported between its ends, and with the lower pet-cock closed and the upper pet cock open and the surplus water displaced into a 'displaced water vessel shown in central vertical section. Fig. 3 is an elevation of a measuring bar used in measuring the displaced water in said displaced water vessel, the latter being shown in central vertical section and the scale bar in position at the end of the standard test. Fig. 4 is a transverse section through thecounterpoise and beam on an enlarged scale. Fig. 5 is the same as Fig. 3 showing the parts in position after the moist aggregate has been tested. Fig. 6 is a central vertical section through the apparatus assembled for transportation by hand. Fig. 7 is an elevation of the apparatus in modified arrangement or assemblage thereof. Fig. 8 is an elevation of the rear side of the measuring bar.

The parts of the apparatus and the functions thereof will be understood by considering the same in connection with the description of the manner of using the same, which is as follows: V

In the lirst place, water or other liquid is introduced into the vessel l0 up to pet cock V-11 shown in Fig. l. It is immaterial as to what the volume or weight of the wateris in said vessel l0 up to said pet cockfll so long as it is constant and that is determined in every operation of this apparatus by the pet.

cock ll. Then the pet cocks V11 and 17A are closed and the vessel `.is suspended by. loop 110 on the counterpoise beam l2 as shown in Fig. 2, which beam is suspended from the center 13 by the support 141. Dry aggregate of a predetermined Weight is then introduced into said vessel 1() and said vessel is suspended on one end of said beam. 'Gn the other side of the center ot the beam, there is a counterpoise 15 which is moved on said beam to the extreme left hand end for the purpose of vrei ghing or balancing this predetermined Weight of dry aggregate.

' rlhe counterpoise beam may graduated With pound graduations so as to nfeight the contents of the vessel 10, but in the most practical Jform of this apparatus that is unnccesscy as is simpler and easier to locate the counterpoise 15 in the desired position on the beam, substantially as shown in Fig. 2, and then introduce dry aggregate into the upper end ot ie vessel 10 until said vessel 10 counterbalances the counterpoise 15.

The operator will know Yxactly when the beam 12 is balanced bv reading the bubble indicator 16 the il nt han-d end of the beam. lffhen the bubble is at the middle of the slot the beam is balanced. lt is unnecessary to previously Wei l `the dry aggregate by other Weighing apparatus because the counterbalance above mentioned automatically accomplishes the desired purpose which renders the operation of the device extremely simple.

rlhe pet cock 11 is located at such position that the Weight ot the dry aggregate introduced therein, as predetermined by the counterpoise, Will bring the Water level above pet coclr 17. The aggregate Will settle into the lower portion of the vessel 10 and the Water will rise to a point above the pet cock 17, substantially as indicated by the dotted line in Fig. 2.

T he next thing to do is to open pet coclr 17 and drain the surplus Water from said vessel 10 above saidpet cocl: 17 into another vessel 18 Which is beside vessel 10 but has separate support, such as the table 19. .Said vessel 18 has a bottom cap or base 2O Tvhich closes the same. The displaced Water is conveyed through pet cocl; 17 to vessel 18 by a short rubber tube 21, as shown in 2.

The next step in the use of "h's apparatus is to measure the displaced ater in vessel 18. rl`hat is done preferablv by the measuring device shown in Fig; 3. ttconsists of a metal bar having secured to its lower end a piston-like member 25 which is insertable in vessel 18 down to the Water. 'Eh bar 25 is pro-vided With one more scale strips 2T and 28. rlhe scale strip 27 is for relatively line material and the scale strip 28 is for relatively coarse material and these scales are provided With graduation marks and numerals indicating percentage of the moisture in the aggregate being tested in terms Wit i ret'- erence to the Weight ofthe dry aggregate. rlhat is, it there is one pound orn Water to six pouncs of dry aggregate, there would be sixteen and two-thirds percent of moisture and that would be indicated by the numeral 6 on the scale 28. The scale strips are longitudinally adjustable on the bar 25 by the tollen ing means:

Said bar 25 is provided With longitudinal slots 29 and thereJ are duplicate scale strips on the opposite side of the bar connected by screvvs 30 Which extend through the slot. By releasing the screws the strips can be longitudinally adjusted to the desired position. rlhese scale strips are located in their proper places by adjusting them so that when the piston-like member 26 rests upon the top ot' the displaced Water in vessel 18 the zero marl; on the scale strip Will register with the top of vessel i8, as shown in Fig. 3.

Scale strip 28, Which is at the left of scale strip 27, is similarly formed, graduated and located but With reference to use for coarse material. @n the back sides of said scale strips 27 and' 28 there are graduations 31 as inv Fig. 8, which indicate gallons of Water per cubic foot of the aggregate measured in a damp, loose condition. The latter scale will be used When the aggregate is to be measured volumetrically and indicates the amount of Water actually contained in one cubic foot of material.

fitter Water ceases to flow through pet cock 17, as above explained, it is necessary to move the counterpoise 15 to the right in order to counterbalance the material and Water then left in vessel 10. This position is indicated by dotted line in Fig. 2.

After the counterpoise 15 has been located in said last-mentioned dotted line position, it is fixed temporarily in such position for use in the remainder of the operations by an adjustable stop 35, shown in Figs. 2 and 4l.

'top 35 extends outward from the scale beam into a longitudinal slot 36 in the counterpoise and then the counterpoise is turned slightly so that the stop enters the recess 37 and holds it from longitudinal movement or displacement along the beam. The slot 36 in the counterpoise 15 preferably extends from end to end but in the beam there is a limited longitudinal slot 136 for longitudinal adjust-ment of the stop 35. The stop is a headed bolt With a nut thereon and the groove 13G is contracted in its outer portion and Wider `in its inner portion, like an inverted T so that the stop can be clamped in adjusted position on the beam attaching the nut thereon Which is accessible through the slot 36 in the counterpoise.

On the opposite side there is a stop 38 similar stop and similarly mounted on the scale beam, and a slot 138 in counterpoise 15, which arrangement is provided to enable the counterpoise to be easily manipulated for setting it for aggregate of different fin'eness and coarseness. Stop 35 and associated parts is for coarse aggregate and stop 38 vis for fine aggregate. y Y I By the foregoing portion of the operation of this apparatus We have determined the proper Weight or location of the counterpoiseV on the scale beam for performing the remainder of the operat-ion.- i

In the next place the vessels l and 18 are both emptied and vessel 10 is again filled with water up to the lower pet cock 11, the upper pet cock 17 is opened and moist aggregate is introduced into the upper end of vessel 10 until the contents of vessel 10 counterbalances the counterpoise in the dotted line position shown in Fig. 2. Before this counterbalancing position is secured however, the Water will have arisento pet cock 17 and the surplus will have overtlowed into vessel 18.

The water now contained in vessel 18 which has just flown out of vessel 10 through pet cock 17 is measured by the measuring device 25 being inserted into vessel 18 until the piston-like member rests on the water therein and the numeral thereon exposed at the upper end of the vessel 18 will indicate the percentage of moisture in t-he aggregate last introduced into vessel 18, see Fig. 5.

By turning the scale bar around, it will indicate the gallons of water per cubic foot in the materials being tested.

The apparatus assembled for transportation, as shown in Fig. 6, within the main vessel 10, has the loop 110 for a handle. The scale bar 25 is introduced therein with the piston-like end 26 at the bottom. The counter-balancing beam or poise 12 and 15 are then introduced into vessel 10 with the hanger 111 in place and with the poise 15 at the lower end. Finally the vessel 18 is inverted into vessel 10 and the -cap 2O at thev bottom of vessel 18 servesas a top cap or closing means of vessel 10. lThis makes a very compact apparatus, which renders the same easilycarried by hand or by vehicle to any place'where it can be readily and quickly again assembled for use.

The foregoing apparatus can be and is further used as a weighing and balancing device for determining iineness modulus of aggregate or for grading the aggregate being used or desired to be used in concrete work.

For the latter use and purpose, the parts of the apparatus are assembled and associi? ated substantially as they are in Fig. 1, eX-

cept vessel 18. As shown in Fig. 7, the measuring bar 25 is inverted and hung upon the vessel 10 so that their combined weight is the same as vessel 10 with the initial charge of water up to the pet cock shown in Fig. 1. The purpose is to dispense with the water in vessel 10 and substitute the Weight of the bar 25 therefor, and, for that reason, the bar 25 should have the same weight as the volume of water shown in Fig. 1. To that end, the piston-like member 2v6on said bar 25 is hollow and has a shot hole 126 in the top thereof so vthat shot 127 may be added to make lthe Weight of the measuring bar 25 identical with the weight of the volumeof Water up to the pet cock 11.

The counterpoise beam 12 is provided with a short scale or a series of graduations in which the graduations represent the percentage of the total weight of the aggregate introduced into vessel 10, as shown in Fig. 1, when the counterpoise 15 is'placed at the end of the beam 12.

The sample of aggregate to be so weighed is run through a standard sieve analysis in which a plurality of sieves of different lineness are employed. The aggregate passing through the finer sieve is introduced into the vessel and the percentage reading taken by means of balancing the counterpoise on the beam 12 for such increment of aggregate introduced, as indicated by dotted line 150 in 7. The remainder of the aggregate is applied to a. coarser sieve andwhat passes therethrough is also introduced into'vessel 10 and the percent reading taken by balancing the counterpoise for such increment. This process is repeated until all of the aggregate has been subjected to the Vsieve analysis and introduced into the container 10 and the percent readinghas been taken of each increment of iineness of material as above explained.

Vhile the foregoing operation and use of the apparatus may seem rather lengthy and complicated, in actual practice it is done very quickly and practically eliminates all chances of error by any operator.

While water is referred to herein as the liquid used, the invention is not limited to any particular liquid as some other kind of liquid might be used in certain situations instead of water. Also moist and moisture are used in the claims hereof toinclude or refer to any liquid or liquid condition.

The invention claimed is:

1. Apparatus for determining the moisture in non-soluble granular material includ` ing a main vessel for containing a knownr Volume ofliquid with an overflow opening in the upper part thereof, a counterpoise beam Vfrom one end of which said vessel is suspended, an adjustable counterpoise on said beam, a vessel adapted to receive the overflowv liquid from said main vessel, and means for'measuring the overflow liquid.

2. Apparatus for determining 'the moisture in non-soluble granular material including a horizontally disposed counterpoise beam, a main vessel suspended from one end of said beam with an overflow opening in the upper part thereof, a counterpoise-slidable on said beam for counterbalancing said main vessel and its contents, means for securing said counterpoise on said beam when in coun- `ter-balancingposition, a displaced liquid Vestion to enable the main vessel to receive a Y known volume of liquid standing up to said lower outlet, a horizontal counterpoise beam supported between its ends and adapted to support said main vessel on one end, a slidable counterpoise on the opposite end, means for securing` the counterpoise to said beam in eounterbalancing position, a displaced liquid vessel, means for conveying the overiiow liquid from the main vessel to the displaced liquid vessel, and means for measuring the contents of the displaced liquid vessel.

4. Apparatus for determining the moisture in non-soluble granular material including a main vessel with an overiiow outlet in the lip-per part thereof, a horizontal scale beam on which said vessel is suspended, a longitudinal slot therein, a'lock nut adjustable in said slot, a counterpoise slidable on and surrounding said beam and having a longitudinal slot therein to render said stop nut accessible, a lateral recess in the counterpoise adjacent the longitudinal slot therein for receiving said stop nut when the counterpoise is turned for holding the couiitei'poise Ain adjusted position to counterbalance the weight Y upper part thereof, a counterpoise beam from of said vessel and its contents, a displaced liquid vessel, means for conveying the' overiow liquid from the main vessel to the displaced liquid vessel, and means for measursel,v whereby the counterpoiseinay be adjusted and held permanently Jfor repeat-ed subsequent use in casting moist aggregate of the saine general character.y

` 5. Apparatus for determining themoisture ininon-soluble granular material including .a main vessel for containing a known volume of liquid with an overflow openingin the one end ofwhich said vessel is suspended,

' an adjustable counterpoise on said beam,` a

vesseladapted to receive the overflow liquid `from said main vessel, and means for measuring the contents of the displaced liquid vessel consisting of a measuring bar insertible therein and graduations thereon indicating the amount of moisture in the moist aggrevate. 4 v H 6. Apparatus for determining the moisture in non-soluble granular material including a main vessel for containing a known volume of liquid 'with an overflow opening in the upper part thereof, a counterpoise beam from one end of whiclisaid vessel is suspended, an adjustable `counterpoise on said beam, a vessel adapted to receive the overflow water from said main vessel, vand means for measuring the contents of the displaced liquid vessel consisting oi a-iiieasuring bar insertible therein and graduations thereon indicating the amount of moisture in the moist aggregate, ,said` scale bar being provided with a plurality7 of .graduations suitable for testing a pluralityrof kinds o' aggregate.

l7. Apparatus 'for determining the moisture in non-soluble granular material including amain vessel for receiving water and aggregate, a counterbalancing beam and poise for weighing' the contents of said main vesselv and'adapted to be inserted in said main vessel when not in use, a measuring bar for measuring the liquid displaced from said main vessel and adapted to be inserted in said main vessel wlienviiot in use, a displaced liquid vessel adapted to be inverted and inserted in said main vessel so as to Vclose the top thereof, and a handle connected with the main vessel whereby the entire apparatus is in and carried by said main vessel for convenient transportation.

In witness whereof, I have hereunto affixed my signature.

ROBERT E. ROBB. 

